1. Field of Use
This invention relates generally to dairy cow milking apparatus and to a method for operating the same. The apparatus comprises a vacuum operated mobile milking unit for milking several cows simultaneously and a vacuum system including a stationarily mounted multiported main vacuum line for supplying vacuum to the mobile milking unit. The method provides for moving the mobile unit from one group of cows to another without interrupting milking operations in progress or interrupting the vacuum supply from the main vacuum line.
2. Description of the Prior Art
Dairy cow milking apparatus presently used in the dairy industry encompasses various types of milking units. However, such units typically employ a milk receiver and at least one teat claw assembly (including a plurality of teat cups) and such units require a vacuum system connectable to operate the teat cups in a pulsed manner and to draw milk from the teat cups to the milk receiver from whence it is pumped to a bulk storage tank.
Milking units may take the form of stationary units, portable units or mobile units.
Typically, several stationary units are placed in fixed locations in a barn and are supplied from a stationary main vacuum line having branch lines to each unit. Such a permanent installation is relatively costly and inflexible.
A portable unit usually includes a single teat claw assembly and milk receiver and is carried by the operator from one stall to another and is connectable to the most conveniently located port of a multiported stationarily mounted main vacuum line which extends through the milking area of the barn. Portable units normally permit milking of only one cow at a time and thus prolong a milking operation and must be carried from one place to another. Furthermore, the portable unit cannot be operated when disconnected from the vacuum system.
A mobile milking unit having a plurality of teat claw assemblies for milking several cows simultaneously and incorporating its own vacuum system, including an electric motor and vacuum pump, is moved from one group of cows to another as required. U.S. Pat. application Ser. No. 600,813 filed July 31, 1975 which issued as U.S. Pat. No. 4,034,711 on July 12, 1977 filed by Bender and Schmid for "Mobile Milk Unit and System" discloses the latter arrangement.
Such a mobile unit is very convenient and efficient but is relatively costly since it contains its own vacuum system. Furthermore, it is not adapted for use with existing installations which employ stationarily mounted multiported main vacuum lines and, even if so adapted, the costly self-contained vacuum system is redundant.